The “file/folder corrupted” error message is indicating that NTFS can’t read the record that describes where a particular piece of data resides. Typically the contents of the file remain intact, which is why the typical fix for this error is also how most users end up losing files.
Every file & every folder within a directory on NTFS has an entry in its Master File Table (MFT). If that MFT entry cannot be read then Windows will report that the file is corrupted, but the file’s contents may actually exist on the hard drive itself.
chkdsk causes it to rewrite all of the file tables so they can be read correctly. However, when entries cannot be reconciled, chkdsk eliminates those entries from the file table. These eliminated entries include the data needed to recover files.NTFS stores an index (or Master File Table) called the MFT. This index contains a record for all of the files and folders including their names, sizes, access control levels, and the physical addresses on the disk where their contents reside. When Windows is unable to read the index entry associated with a particular file or directory requested, Windows will report that the file/directory has been corrupted and thus unreadable.
Consider this. Windows states the file’s/directory’s description could not be read. There was no statement regarding the integrity of the files’ contents which were likely good but were now inaccessible due to damage to the map referencing them. The difference between a damaged description and damaged contents is the primary reason recovery works on damaged systems.
The most frequent source of corruption on an external drive is pulling it out (or disconnecting) from your computer while Windows was in the process of writing to that device; this causes the update to the file table to be halted somewhere along the way leaving the file table with inconsistencies. When a power loss happens with an internal drive, a similar thing occurs as well. In either case, neither one necessarily represents a hardware issue, and many times they are fully recoverable.
A second possible reason is that there are bad sectors, where the portion of the hard drive containing some or all of the MFT (Master File Table) can no longer be read reliably. This is typically a hardware issue and tends to grow in severity as time goes by, dramatically increasing the sense of urgency. The two scenarios differ fundamentally from each other: a single item (folder or file), damaged after being pulled out improperly and then plugged back in, versus multiple items becoming corrupt and developing over time on a disk that is slowing down due to failed areas.
chkdsk’s job is to create a viable file system, not to save your data. When chkdsk locates an item that it cannot find a way to make compatible with the rest of the file system it may delete the entry, cut off access to parts of the file or move them into found.000 as numbered files without names. In general this is a good trade-off when using chkdsk on a nearly-healthy drive with minor problems, but using it on a drive with many bad sectors is not because there are two issues with doing so: first, you are writing data to a disk that is having trouble reading, and second, running chkdsk /r does a full-surface scan (hours of exactly the worst kind of stress).
If the drive is slow, noisy or throws lots of errors then using chkdsk is the one thing most likely to make things permanent.
Attempt to read the drive on another computer, and start copying off anything you can (beginning with what you would be saddest about losing) but realise that some files are going to fail. If it’s an external unit, begin by attempting a different cable/USB port as well because a dying bridge will produce this failure message on a completely fine hard drive.
In cases where the drive has failed, recovering the data involves making a non-writeable image of the contents beyond the damaged area(s), and rebuilding the file table from that copy so that the original is not ever written over. The cost of recovering a single drive is from £300 +VAT after a complimentary 48-hour diagnostic period. In most cases you only pay if we recover your data.
That NTFS couldn’t read the master file table (MFT) record describing that file or folder: its name, size and where on the disk it’s stored. This means the index entry of the file or folder (not the data itself) can be damaged but the data on the disk may still be recoverable.
Only if you are confident the drive is healthy. chkdsk is primarily concerned with having a consistent file system, therefore it will delete/truncate any entries it has issues reconciling, and the /r option performs a full surface scan. Running chkdsk on a failing drive is the single action most likely to result in your loss being permanent.
Most often, external drives removed while Windows was writing or a power failure mid-update; this leaves your file table inconsistent. The other cause for this issue would be bad sectors in the region holding your MFT, which is a hardware fault and tends to spread.
Typically. The image of the drive is taken read-only and the file table will be recreated using this copy or individual files will be “carved” out of the copy based on signatures when the original table is too far gone. Because the original is never written to, nothing that happens during the recovery process can make things any worse than they already were.
A standard (single) drive costs from £300 + VAT. A written quote will be produced within 48 hours of sending a drive to us for our free initial diagnostic. In most cases you only pay if we recover your data. Please send external drives complete with their enclosure rather than removing the disk.